What is the general opinion about using different sizes of kits? Of course I realize that it's always preferable to carry large kits all the time but lets say if that is not possible, what kind of tanks should be carrying large kits as opposed to small ones? Can certain tanks do just as well with small kits as large ones?

On tanks that are prone to suffer ammo rack damage from sprocket wheel shots like E5, I'd take a large kit. On tanks that rarely suffer from multiple damaged modules like E-50M... I'm a cheap ass that use small.

On tanks that often lose multiple crew members (from eating HE shells) like Grille 15, I'd use a large kit. On tanks that rarely lose any crew member other than the driver like IS-4, small kit works just fine.

Unless you find that you're having issues with multiple modules/crew being hit at once, small kits are usually fine. On the rare occasion that a second module is destroyed, you can still stall out the recharge, and generally speaking you won't have many issues.

I only use a large repair kit on the E5 (drive wheel+ammorack) and a large repair kit on the Object 140 (tracks+ammo+fuel+engine+literally everything else that can be damaged).

This may not be smart, but on tanks which aren't prone to fires, or tanks where repair speed is the difference between surviving/not (e.g. scouts), I sometimes carry both repair kits and don't carry an AFE. I use the small to repair what needs to be repaired instantly, carry the large for emergencies and the bonus to repair speed. I pretty much always carry a small med kit, and with the recharge that's usually fine. I don't even bother healing a radio operator for the most part.

Most of the time it's about how fast you can repair your track anyway, with CD consumables you can afford to run a small rep without it costing as much as it used to.

If you cant repair a track fast enough to get hit once more - its already cost you the credits you "saved" with small kits. It means less HP to use so less damage and a higher chance of dying.

Ammorack+sprocket shots are a huge thing too so it'll end up costing damage with a small kit no matter which one you choose to repair.

There are a few tanks that don't really take combined module damage so there small kits wont cost you as much, but the speed of repairing still matters (autoloader ammorack will lose out possible shots easily if the rack isnt instantly repaired since you get an extra second rld per second unrepaired)

Med kits are much nicer though, you can run small on basically everything unless you get shafted by commander/gunner/loader combos, if you have JoAT then this is a lot nicer on you too so I still advice big reps at least on anything you want to be competitive in, where medkits can be worked around enough to still be acceptable using small ones.

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That warm, fuzzy feeling when you're sidescraping so well the three enemy tanks you are engaging resort to shooting HE with low caliber weapons. And then the feeling when a "friendly" TD blats you in the back from the redline, causing you to get killed.